Question

为什么它会在行中显示错误：分段[] =新的Coord（行，列）;结构者？

public class TreasureMap{
    int rows, cols;     // How big is the treasure map
    Coord [] treasureLocations; // The locations of treasures

    Scanner kbd = new Scanner(System.in);
  // Prompt the user for info on the treasure map and then create it
  // COMPLETE THIS METHOD
  public TreasureMap(){

      System.out.println("Enter the map size (2 ints): ");
      rows = kbd.nextInt();
      cols = kbd.nextInt();
      treasureLocations[] = new Coord(rows, cols);




public class Coord {
  public final int row;
  public final int col;

  // Constructor, 
  public Coord(int ir, int ic){
    this.row = ir;
    this.col = ic;
  }

Answer 1

treasureLocations[] = new Coord(rows, cols);

这一行不是有效的语法。您需要通过在方括号内放置一个int值，将新对象分配给数组内的位置。像这样：

int position = 0;
treasureLocations[position] = new Coord(rows, cols);

您还需要初始化数组。查看程序的顶部，您已经声明了它但未将其分配给任何程序，因此在运行时您将获得空指针异常。像这样：

Coord [] treasureLocations = new Coord[someNumber]; // The locations of treasures

Answer 2

新的Coord（......，...）之后; 把＆＃34;}＆＃34; 然后在线上。

你正试图制作一个阵列＆＃34; []＆＃34;只有一个Coord。

构造函数有什么问题？

2 个答案: